A large survey of nurses found numerous examples where the junior staff, known as 'HCAs' on wards, were put in charge of jobs strictly speaking beyond their capabilities.

These included administering certain restricted drugs and caring for potentially vulnerable patients in intensive care.

The claims, highlighted in the survey by Nursing Standard magazine, yet again raise worries about the standard of care some patients are receiving.

The NHS Future Forum, an independent advisory panel, published a report on Tuesday warning that some nurses lacked the basic skills and attributes for the job, such as numeracy and a caring attitude. More rigorous selection was needed to ensure the quality of nursing, the forum concluded.

Professor Sir John Tooke, a panel member who himself wrote a far-reaching report on doctors' training five years ago, told The Daily Telegraph that nurses also needed to have role models who were actively involved with caring for patients on a day-to-day basis, as doctors did.

Admitting to "deep concerns" about the nursing profession, he said: "The bulk of nurses don't see people at the top of the profession actually nursing, they see them doing something else. But we know that in medicine, role models are crucial."

He added: "We need to develop the concept of the ward sister, rather than the ward manager."

Dr Peter Carter, chief executive and general secretary of the Royal College of Nursing, said the Nursing Standard's survey findings "add further weight to the case for mandatory regulation and guaranteed training standards for healthcare assistants".